Little Mix's Jesy Nelson welcomed twins last year. Then her mum sensed something wasn't right.

When former Little Mix singer, Jesy Nelson, was finally able to take her twins home, she was excited for life as a new mum.

Her twin daughters, Ocean Jade and Story Monroe, were born prematurely at 31 weeks on May 15, 2025 and spent an extended stay in the NICU.

Doctors warned Jesy, 34, and her fiancé, Zion Foster, not to compare their daughters' milestones to other babies because they were premature.

"I was told, take them as they are, and they will get to where they need to be when they do," Jesy said in an emotional Instagram video.

So it didn't immediately raise alarm bells when Jesy's mum noticed the girls weren't moving their legs as much as they should be.

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"I'd been told don't compare your babies to other babies… and when the health care visitors came, we were told 'they look great, they're healthy, everything's fine," she said

But as time went by, it became increasingly clear that the twins lacked leg mobility and were beginning to struggle to "feed properly."

Following months of medical consultations, the eight-month-olds received a life-altering diagnosis.

"After the most gruelling three, four months, and endless appointments, the girls have now been diagnosed with a severe muscular disease called SMA type 1," Jesy shared with her followers in the video.

SMA Type 1, also known as Werdnig-Hoffmann disease, is the most common and severe form of SMA. It is a rare genetic condition that causes progressive muscle weakness because the nerve cells in the spinal cord and brainstem (motor neurons) do not work properly.

Fighting back tears, Nelson shared the gravity of the diagnosis, noting that the condition fundamentally attacks the body's motor functions.

"Essentially, what it does is, over time, it kills the muscles to the body, and if it's not treated in time, your baby's life expectancy will not make it past the age of two," she admitted.

Watch a news segment on the dangers of SMA. Post continues after video.

The outlook remains challenging, as doctors informed the couple that the girls will "probably never walk" and likely "never regain their neck strength so they will be disabled."

Nelson noted that "the best thing we can do right now is to get them treatment and then just hope for the best."

Since the diagnosis, they have begun a rigorous medical routine. "I have to put them on breathing machines and do lots of stuff that no mother really should ever have to do on their child," she said.

Reflecting on the sudden change, she said: "I almost feel like I'm grieving a life that I thought I was going to have with my children."

Despite the prognosis, Jesy remains hopeful that her daughters will "defy all the odds" and with the right help, "they will fight this."

Nelson rose to fame on The X-Factor UK as a member of girl group Little Mix, who went on to find huge success both in the UK and abroad. She departed the group in 2020 and has since pursued a solo career in music.

By sharing her experience, Jesy hopes to urge other parents to act quickly if they notice similar symptoms, emphasising that early intervention is vital for babies with SMA, which she reiterated is "the most severe muscular disease that a baby can get."

Feature image: Instagram/@jesynelson.